UK · Research-grade · Cold-chain

Tirzepatide vs semaglutide — the honest UK comparison.

Two of the strongest weight-loss peptides in the space, compared on the thing that matters: the trial data. Every figure below comes from our own product pages — no marketing math, no invented superiority. Read the table, then pick the one that fits your goal.

Tirzepatide pricing Semaglutide pricing

01 · Head to head

The full comparison, cell by cell

Every cell is anchored to the product pages — pathway, evidence, trial figures, titration, vials, side effects. If it's not on a product page, it's not in this table.

	Semaglutide	Tirzepatide
Pathway	Single: GLP-1 receptor agonist (Ozempic/Wegovy molecule)	Dual: GIP + GLP-1 receptor agonist (Mounjaro/Zepbound molecule)
Evidence grade	Grade A — STEP, SUSTAIN, SELECT programs	Grade A — SURMOUNT-1, SURMOUNT-MASH, SURPASS-CVOT
Headline trial figure	STEP-1: −14.9% body weight at 68 weeks; STEP UP up to −20.7% at higher dose	SURMOUNT-1: −20.9% to −22.5% body weight at 72 weeks, dose-dependent
Titration ceiling	0.25 → 0.5 → 1 → 2 mg weekly, up to 2.4 mg (higher-dose trials to 7.2 mg)	2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg weekly; TR50/TR60 vials for high-dose
Vial range	10–30 mg	5–60 mg
Side-effect profile	Early self-limiting nausea, constipation; rare pancreatitis/gallbladder signals	Nausea, constipation, injection-site reactions; rare pancreatitis signal — a spectrum similar to semaglutide
Who each fits	The proven, deepest-evidence option; a sensible first pick	The dual-pathway option with the larger trial numbers; the premium pick from the start

02 · How to choose

Three honest ways to decide

No invented superiority claims — this is the trial data plus what the product pages say about the path between them.

If you want the proven track record

Semaglutide has the deeper evidence base — Phase 3 programs across STEP, SUSTAIN and SELECT, including the SELECT cardiovascular outcomes trial (MACE reduction). The most-evidenced peptide in the metabolic space, on our own product page.

If you want the maximum weight-loss numbers

Tirzepatide's SURMOUNT-1 ran −20.9% to −22.5% at 72 weeks, dose-dependent — the class-leading figures in the sources. Two gut-hormone pathways instead of one is the mechanism behind it.

If you're not sure yet

The path the product pages themselves describe: many start on semaglutide and step up to tirzepatide if they plateau. You lose nothing by starting with the option that has the deeper evidence.

03 · The shared caveat

Lean mass — the part both sides leave out

Applies to both peptides, and it's the difference between a scale number and a body composition you'll actually keep.

From the semaglutide product page: in body-composition work, a portion of the lost weight is lean mass — worth pairing with protein and resistance training. Whatever you pick from this table, that pairing is the part that decides whether the number sticks.

04 · Ordering

How to order either one

Per-vial pricing on both, same payment paths, same delivery.

Per-vial, no minimums

Semaglutide vials run 10–30 mg; tirzepatide 5–60 mg. One vial is a valid order on either.

Bank transfer — save 10%

Same lot, same delivery, whole order 10% off. Quote your order number as the payment reference — that's the step people miss.

COA in the box, cold-chain to your door

Every batch ships with its Certificate of Analysis — tracked, insured, UK-wide, next working day dispatch. WELCOME10 stacks on your first order.

06 · Straight answers

The questions people actually ask

Which one should I start with?

Many start on semaglutide — single pathway, the deeper evidence base — and step up to tirzepatide if they plateau. That path comes straight from the product pages' own FAQ. If you want the strongest dual-pathway option from the start, tirzepatide is the premium pick.

What does 'dual pathway' actually change?

Tirzepatide targets two gut-hormone receptors (GIP and GLP-1) rather than one. In trials that translates to greater appetite suppression and weight loss — SURMOUNT-1 ran −20.9% to −22.5% at 72 weeks versus semaglutide's STEP-1 −14.9% at 68 weeks.

Are the side effects different?

Similar spectrum: nausea, constipation, injection-site reactions, and a rare pancreatitis signal on both. The product pages describe tirzepatide's profile as 'a spectrum similar to semaglutide.'

What about the vials and dosing range?

Semaglutide vials run 10–30 mg with titration 0.25 → 0.5 → 1 → 2 mg weekly, up to 2.4 mg (higher-dose trials to 7.2 mg). Tirzepatide runs 5–60 mg with titration 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg weekly — the higher-strength TR50/TR60 vials suit high-dose users.

Does it matter how I pay?

Same vials, same lot. Bank transfer takes 10% off — quote your order number as the reference. No minimums on either peptide, and WELCOME10 stacks on your first order.